The only known photograph of late rock stars Phil Lynott and Rory Gallagher performing together has been re-discovered after 28 years.

The image, taken at an open-air concert at Punchestown Racecourse in July 1982, was only unearthed two weeks ago by photographer Colm Henry.

Once Ireland's top rock photographer, the Meath man spent the 1980s photographing some of the biggest names in music, both at home and abroad, and is now rediscovering these images as he trawls his huge archives for a new gallery.

Mr Henry said moving house over the years has resulted in him mislaying many of the images he has shot over the decades.

"I still have the negatives but many of my proof sheets are gone. In the case of the picture of Phil Lynott and Rory Gallagher together in 1982, I found it in a file of Phil Lynott images from 1986."

"Thin Lizzy weren't even playing at that concert. Phil Lynott just turned up and decided to get onstage with Rory. It's not like Oxegen now. Things were a lot looser back then and that could happen," Mr Henry said.

A doe-eyed Sinead O'Connor awaiting her flight in Dublin Airport in 1985 is another striking image from Mr Henry's collection.

"Sinead was going over to London to sign her first record deal. I had given her a lift to the airport. That's the way it was in Dublin in the '80s. Sinead told me recently she regards this picture as capturing a seminal moment in her career," added Mr Henry who also captured iconic shots of U2 and The Blades.

Visiting rock stars came under Henry's lens too -- he photographed songwriter Leonard Cohen here in Jury's Coffee Dock Inn in the early 1980s.

"The great thing about when big acts came to Ireland in the 1980s is that they arrived with no handlers and no entourage, this meant they were very open to suggestion.

"I can remember, rather than being quiet, Leonard Cohen didn't stop talking about his new girlfriend, an Italian fashion designer. He really was in love back then," said Henry.

He also captured David Bowie onstage at Slane and Sting on Killiney Hill, but the opportunity to photograph visiting rock stars dried up for Mr Henry in the early 1990s.

"Access to artists stopped because merchandise lawyers took control of the bands. At the same time I wanted to move on. I began to work in theatre, and then later for 'VIP' magazine doing glamour shoots, " he said.

However, now aged 57, Colm Henry has gone back to rock -- opening a gallery of his iconic rock images in Dun Laoghaire Shopping Centre this week and uploading his latest 1980s finds on to website www.colm henry.ie.